What are the inheritance rules when spouses have children from a previous marriage? Can my house be in a trust for my children's benefit but also still benefit my husband? Is there a time-frame after which a prenuptial agreement becomes inapplicable or open to dispute? Should I ask my husband to sign an agreement waiving his right of election to any part of my estate, and vice versa?

The inheritance rules protect your spouse, not your children. Under New York's "right of election," your surviving spouse is legally entitled to $50,000 or one-third of your assets, whichever is greater, no matter what your will says.

A husband and wife who don't like this rule can sign a prenuptial or post-nuptial agreement -- a contract in which they both waive their right of election in favor of a plan they've created to fit their own situation. In a second marriage, these agreements protect both spouses while also safeguarding the inheritance of their children from previous marriages. For example, you might leave your house to your children, but give your husband the right to continue living there for his lifetime.

An agreement can include a sunset clause saying it will no longer apply after a certain number of years. But it should never be open to dispute.

To be legally valid, the agreement must be fair to both spouses. Both of you must disclose all your assets to ensure that neither of you unwittingly signs away his or her entitlement to one-third of a fortune. And each of you must have his or her own lawyer. Courts take a dim view of a contract between two parties who were represented by the same lawyer.

THE BOTTOM LINE A prenuptial or postnuptial agreement can safeguard the inheritance of your children from previous marriages.

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